Grinding and polishing machine



March 6, 1934. Q 1 HAWES 1,950,030

GRINDING AND POLISHING MACHINE Filed June 27. 1931 3 Sheets-Sheet 1 w CHA m 15 4. HA w55 @K S BY Mw@ T7 A TTORNEYS Mamh e, 1934. C HAWES 1,950,030

GRINDING AND POLISHING MACHINE Filed June 27. 1931 5 Sheets-Sheet 2 CHA El /E L HA WES A TTORNEYS INVENToR.

4March 6, 1934. c. HAwEs GRINDING AND POLISHING MACHINE Filed June 27. 1931 3 Sheets-Sheet 5 INVENTOR.

CHARIL/E L .HAWES --VLA i A TTORNEYS.

patented Mar. 6, 1934 UNTE; STATES TENT -i Claims.

This invention relates to machines for grinding, polishing, buffing, and similar' operations, said machines being of the type wherein several grinding and/ or polishing or similar elements are 5 mounted at intervals along a conveyor, the work being carried by said conveyor beneath the various wheels in succession. rlhis type of apparatus may be of any desired length, usually in the neighborhood of twenty to eighty feet, and

l0 the wheels are usually arranged to form a progression as to character of the work done; for example, the wheel at the first station or first few stations will be rough and the succeeding wheels finer, so that if the machine is long enough and has a sufficient number of stations, work may be completed from a rough to a polished condition in a single passage through the machine.

In this type of machine the means for driving the conveyor and the mechanism used at each station are to some extent independent, and the present application has reference to the latter.

In the specification and claims the words grinding and polishing are used to illustrate the invention and not to limit its scope, inasmuch as the aims and purposes of the invention relate to any surface conditioning operations for which the mechanism is or may be found to be suitable.

My invention aims particularly to provide accurate and efficient control for the pressure applied at the lgrinding or polishing wheel and for the vertical positioning of said wheel. Another aim is the provision of a machine of this type wherein the angular relation of the wheel to the work in progress can be adjusted; the provision ci means for making changes in the range of work for which the machine is adapted; the provision of means for moving any unit out of operative position quickly and holding it there as long as desired without necessitating any readjustment of parts when the machine is put back into operation.

Other aims and purposes or" the invention will appear from the following description and the accompanying drawings. To the accomplishnient of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings:

Fig. l isa central, vertical, longitudinal section through my machine; Fig. 2 s a transverse vertical section on the line 2-2 of Fig. l, looking in the direction of the arrows; Fig. 3 is a pia-n View oi the machine also indicating the horizontal angular positioning which can be effected; Fig. 4 is a detail of the elevating mechanism, on the line 4-4 of Fig. l, in the direction of the arrows; Fig. 5 shows various sizes of spacer blocks, on the same plane as Fig. 1; Fig. 6 is a vertical, central, longitudinal section showing a modified form of grinding head support and lifting means; Fig. 7 is a View corresponding to the upper portion of Fig. 2 but showing the same form of grinding head and support as is shown in Fig. 6; and Fig. 8 is a diagrammatic illustration of air controls for the form of apparatus shown in Figs. 6 and 7.

rhe machine is supported on a pedestal or base l which is preferably a hollow casting having a table top- 44 with downward edge anges 40 to which extensions, such as 32, may be bolted, forming a long continuous table, over one side of which the conveyor belt 45 travels through guides 46. A. base plate 17 which rests movably on the table 44 has a spacer block 18 bolted thereto, this block supporting a bracket 20, on which an arm 47, disposed lengthwise of the conveyor belt 45, is horizontally pivoted by the pin 48. The arm 47 carries at one end a grinding or polishing wheel 49 and its associated mechanism, and at the other a driving motor 3l and counterweights 43. Beneath the wheel mechanism, and suitably connected thereto, a iioat 4 supported by liquid 50 within the pedestal l. The movement of the plate 17 is such that the grinding .vheel 49 can be swung into angular relation to work passing under it on the belt 45, as apparent from Fig. 3, while the pivot 48 permits up and down movement of the wheel. The pressure of the wheel on the work is controlled by the counterweights 43 and also by the float 4.

Referring now in more detail to the various eiements outlined above, the top of the table 44 is cut away as indicated at 51 leaving a circular opening of considerable size in the top of the base l. A plate 10, approximately flush with the table top, ts therein, but is dependently supported from the base plate 17 which is consequently pivoted for movement in a horizontal plane about said opening. The plate 17 extends in one direction as a large heavy construction which supports the grinding and driving elements of the mechanism and which terminates in a iiange 52 of an arcuate plan concentric with the opening 51, which rides under a clamp 21 and can be held fast upon the table extension 32 by such clamp. At the other end, the plate 17 is cornposed of a relatively narrow rim 53, also arcuately concentric with 51 and adapted to be held stationary by a clamp 14. The larger portion of the plate 17 is internally slotted as shown in Fig. 1 for the reception of a T-shaped bolt 41 which merely serves as an additional clamp.

This larger part of the plate acts as a foundation for a spacer block 18 of any convenient construction having preferably a flat top surface to carry a bracket 20 which may be secured by through bolts such as 54 to the base plate 17. These bolts 54 serve as a suflicient holding means for the block 18 also. On its end toward the vertical axis, the topI surface of the block 18 serves as a shelf for a positive limit stop 19 for the arm 47. To adapt the machine for wide variations in ranges of work the books 18 are readily removable by taking out the bolts 54, so that other blocks such as 18 or 182, Fig. 5, of different heights may be substituted.

The bracket 20, which may conveniently take the form of a transverse angle having a reinforcing web and an internal bearing at the top, carries a through horizontal pin 48, about which the arm 47 may move in avertica-l plane. It will be understood that the bracket 20 is single but has two bearings inside of the arm 47.

Considering the arm 47 in detail, it is a composite structure, consisting of a unitary element extending to the right of the pivot 48 in Fig. 1 and carrying the grinding wheel 49 and its immediate associated mechanism at the far end, but having a transverse plate or apron 29 secured to an upward and rearward extension 56 above the pivot 48 by two horizontal bolts 28 which act as pivots. This plate 29 is the mounting for the drive motor 31, and is adjustable about the pivot 28 by means of a pair of screws such as 30 which bear against a lower element 57 of the front part of the arm. A balance bar 42, conveniently secured to the motor apron 29, is shown in Fig. 1 as extending horizontally to the left and carrying adjustable counterweights 43, 43. For certain types or" operation, this bar 42 can be reversed in position and extended forwardly.

The mechanism associated with the grinding wheel is particularly seen in Fig. 2 and comprises a transverse shaft 23 mounted by appropriate bearings in a housing 25 formed on the end of the arm 47. These bearings are here shown as oil-tight and the housing is indicated as constituting an oil reservoir which` may be tted with plugs 58. Lubricating chains 22 of the type shown by my United States Patent No. 1,334,535 are illustrated as applied to this construction. One end of the shaft carries a pulley 59 connected by belt means 60 to a pulley 61 on the motor. It will thus be apparent that the tightness of the belt is controlled by the screw adjustment 30. The other end of the shaft 23 is considerably extended to receive grinding, polishing, buflng or other similar wheels of various sizes, to be clamped thereon by any usual means such as the washer 61 and nut 62.

It will be apparent from the foregoing that the entire mechanism which has been generally designated by the reference character 47, including the wheel 49 at one end and the motor 31 at the other, is so mounted as to move about the horizontal pivot 48 without altering the relations of any of the parts among themselves. It is also apparent that the motor 31 serves as a counterweight to the wheel. From this it may result that in order to press the wheel upon the work with sunicient force, it will be necessary to reverse the position of the bar 42 so that the counterweights supplement the weight to the right of the pivot 48. In order to limit positively the possible movement of the wheel 49 toward the work, the limit stop previously mentioned is provided. This limit stop is situated in an opening 63 in the arm element 55 and rests upon the block 18 as previously mentioned. It comprises an upstanding tube to which the reference character 19 is particularly applied, this tube resting by the base flange 64 on the block 18 and having a longitudinal slot 65 in one side and an internally threaded upper portion 66 of restricted diameter. A tube 26 telescopes over the tube 19. This tube carries a lug 67 at one side engaging under a web 68 of the arm element 55 at one side of the opening 63 and also carries a stud 69 sliding into the groove 65. The height of the lug 67, and consequently the downward limit of motion of the arm portion 55 is governed by a threaded shaft 70 which takes in the threads 66 and carries a top flange 71 engaging the inturned upper end of the tube 26. The shaft has an upwardly extending shank carrying a hand wheel 27 whereby it may be rotated. A spring pressed detent 72, having a rounded nose, takes into a shallow depres- -sion in the top of the tube 66 to prevent accidental rotation of the hand wheel, but the shape is such that the detent will ride out of the depression when the wheel is intentionally turned with some force.

A further means of adjusting downward pressure of the grinding wheel 49 and also of preventing any pendulum motion which might be set up by the gyroscopic action of the wheel 49 is provided by the float 4 and its connections, which will now be described.

The base 1 being hollow constitutes a tank which may be lled to a suitable level with oil, water or other liquid such as 50 to support the iloat generally designated as 4, which however also carries buoyant side members 3. The central portion of the iloat is of such a size that it can be introduce-d through the opening 51, while the side members 3 are smaller and may be attached to the main float after the latter has been placed in position. The central float has a tube 7 upwardly extending permanently secured through and to it. A guide rod 2 fastened to the bottom of the tank extends up into this tube. The tube 7 passes up through an opening in the center of the plate 1G and is guided therein by a ring of bearing rollers 11. The top of the tube is closed by a plug 8 permanently positioned to which is fastened the lower end of a rod 16, vertically disposed, the upper end of which rests in a socket in the lower side of the housing 25. The upper and lower ends of the rod 16 are preferably ball joints in shallow sockets to allow the necessary angular movement as the float rises and falls.

A dust guard, such as the bellows 9 covers the upper part of the rod 7 and prevents entrance of dust and grit to the tank. A tank iilling plug 15 is provided, and a drain plug (not shown) may be fitted in the bottom.

It may happen in using a long row of these machines that it will be desirable to put one or more out of commission without stopping the travel of the conveyor or the action of the other machines. Means for this are provided by having a cord or chain 36 attached to the roller and dropping down through a slot in the table 32 to i 36 is wound up, the grinding or other wheel will be raised in the air, the ball at the top of the rod 16 following and remaining in contact with the socket in all positions. While the wheel is in its elevated position it may be changed, adjustments being made, and so on.

Instead of the support just described for the right hand extension of the arm 47, the construction shown in Fig. 6 may be used. In this figure the extension corresponding to 55 in Fig. 1 is designated as 55 and comprises a housing 25', the opposite ends of which support a grinding wheel shaft 23. This shaft with its bearings, oil supply chains 22', pulley 59' an-d wheel 49 is the same in all particulars as that in Figs. l and 2, with the exception that the bottom of the casting 25 is horizontal. The top of the float tube 7' is closed by a peripherally flanged plate 8' from the lower face of which a short stem seats in the tube 7'. On the upper face of the plate 8', within the peripheral rim, a bearing 16', which may conveniently be formed of a flat plate constituting a cage for a number of balls, is freely disposed. A plate 16" larger than the plate 8' and having a downward peripheral flange rests freely on the bearing 16', while the bottom of the housing 25' in turn rests freely on the upper surface of the plate 16". It will thus be seen that the arm 55' will normally have a floating support on the plate 16" in the same manner that the arm 55, as already described, has a floating support on the upper end of the rod 16. The form shown in Figs. 6 and 7 does not require as close arrangement between the housing and support as is necessary in Fig. 1.

In order to lift the grinding wheel off the work I may onnt the lifting cable 36 and the various drums and pulleys associated therewith and actuate the elevating mechanism by compressed air, shown in Figs. 6 and 8. In Fig. 6 the central vertical cross section of an air lift is illustrated, the air lift there shown being a substitute for the .ianual down stop shown in Fig. 4, in addition to its function as an elevating means.

This mechanism comprises a central stem 19 resting on the block 18 by an enlarged foot 64. The stem 19 is centrally apertured as at 80, this aperture being open at the top and being entered at the bottom by a exible air supply line 81. An outer cylinder 26', smooth inside, externally threaded, and carrying a hand wheel 27' at the top, nts over the stem 19. Suitable packing means 82 on the upper end of the stem 19' make an air tight joint with the inner walls of the outer cylinder 26. This outer cylinder 26' carries externally a collar 67' internally threaded, but held by suitable means not shown, against rotation, with the result that the collar is movable up and down by rotation of the hand wheel 27'. A spring pressed detent 72' radially and horizontally disposed in the lower end of the cylinder 26 bears against the stem 19' to hold the cylinder 26' in any position in which it may have been set by the hand wheel 27' but not strongly enough to prevent lifting of the cylinder 26 by air pressure.

The arm 55 being formed in the same manner as the arm 55 of Fig. l, has a horizontal nn 63', engagement of which with the upper surface of the collar 67' limits downward movement of the grinding head. To lift the grinding head, air is admitted to the line 8l, thereby lifting the cylinder 26' and bringing the collar 67' up against the fin 63. The portions of the arm not shown,

. at the left of Fig. 6, are the same as in Fig. l.

Thus the screw 30 bearing against the stop 57 prevents excessive lift of the arm.

This air lift arrangement adapts itself either for lift of the heads individually or simultaneously. A valve arrangement for this selective method of operation is diagrammatically shown in Fig. 8 in which the several air lines 81 are individually valved as at 83 to a supply line 84. On this arrangement a second supply line 85 is bypassed as at 86 into the lines 8l so that all the grinding heads can be simultaneously lifted by admitting air through a single Valve 87. Each of the by-passes 86 is ntted with check valve 88 to prevent escape of air to the simultaneously lifting system when any of the individual valves 83 is opened.

The operation of the device is thought to be fairly apparent from the foregoing description, but it may here be mentioned that this mechanism presents the possibility of a wide variety of adjustments by rotating the plate 17 about the central vertical axis, the angular relation of the wheel Li9 to the work may be varied as indicated in Fig. 3. By substituting the blocks 18 of varying heights, the proper adjustment may be made for work of diiferent sizes and wheels of different sizes. The weight with which the wheel bears on the work can be altered by adding or removing counterweights and by changing their position, but also by the addition or removal of liquid in the tank to change the buoyant effect of the float and may be further changed by removing supplementary floats 8. Besides the buoyant effect, the float system acts to some extent as a dash pot, preventing violent motion up and down of the grinding wheel.

Other modes of applying the principle of my invention may be employed instead of the one eX- plained, change being made as regards the mechanism herein disclosed, provided the means stated -v by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

l. A grinding and polishing machine coinpris- 1 1 ing in combination, a belt adapted to convey work, and a plurality of grinding or polishing units mounted in operative position above said belt, means for adjustng each of said units both horizontally and vertically, said Vertical adjusting ,i

means comprising counterweights and a combined ioat and dashpot.

2. A grinding machine of the class described, comprising in combination a conveyor, a base,

means at the top of said base for supporting a one end a grinding wheel and at the other end driving means for the same, adjustable balance means on said arm, positive means between said arm and said bed plate for limiting downward movement of said arm, and tank means in said base for resiliently supporting said grinding wheel arm.

3. A grinding machine of the class described, comprising in combination a conveyor, a base, means at the top of said base for supporting a part of said conveyor, a tank within said base, a bed plate rotatable upon the top of said base, a bracket carried by said bed plate, an arm pivoted to said bracket and movable in a vertical plane, said arm carrying at one end a grinding wheel and at the other end driving means for the i.'

Led

same, adjustable balance means on said arm, positive means between said arm and said bed plate for controlling movement of said arm in one direction, and means in said tank connected to said grinding means for damping the Vibrations of said arm and partially supporting the same.

4. A surface conditioning machine of the class described, comprising in combination a conveyor, a base, a table supported by said base, said table supporting a part of said conveyor, a tank within said base, a bed plate rotatable upon said table, a horizontal pivot carried upon and above said bed plate, an arm carried by said pivot, said arm carrying at one end a surface conditioning wheel and at the other end driving means for the same, balance means adjustable as to position on said arm, positive means between said arm and said bed plate for limiting the movement of said arm in one direction, and means in said fluid receptacle for damping the vibrations of said arm and partially supporting the same and connecting means between said damping means and said surface conditioning means located upon the horizontal axis of rotation of said bed plate.

5. In a surface conditioning machine in coinbination, a surface conditioning wheel, an arm supporting the same, a bed plate on which said arm is supported in xed horizontal relation, a table whereon said bed plate can be turned about a vertical axis, a base supporting said table and constituting a tank,acircularopeningthrough the top of said table into said tank disposed with said vertical axis cent-ral thereto, a portion of said table revolubly mounted therein and depending from said bed plate, a central aperture through said portion and a tube extending down through said aperture, means whereby said tube supports said arm, anda float supporting said tube.

6. In a surface conditioning machine, in combination, a surface conditioning wheel, an arm supporting the same, a bed plate on which said arm is supported in fixed horizontal relation, a table whereon said bed plate can be turned about a vertical axis, a base supporting said table and constituting a tank, a circular opening through the top of said table into said tank disposed with said vertical axis central thereto, a portion of said table revolubly mounted therein and depending from said bed plate a central aperture through said portion and a tube extending down through said aperture, means whereby said tube supports said arm, a float supporting said tube, said float being of a size to slightly clear the internal walls of said receptacle, said float being built of elements no one of which is larger than said central opening, but said float as a whole being larger than said opening.

7. A surface conditioning machine of the class described, comprising in combination a conveyor, a base, a table supported by said base, said table supporting a part of said conveyor, a tank within said base, a bed plate rotatable upon said table, a horizontal pivot carried upon and above said bed plate, an arm carried by said pivot, said arm carrying at one end a surface conditioning wheel, a float in said tank, liquid in said tank, a rod connecting the wheel-carrying end of said arm with said oat, a restricted passage between the side of said float and the side of said tank whereby said float may act as a dashpot, and means for varying the size of said float.

8. In a surface conditioning machine, an arm movable about a horizontal pivot, a surface conditioning wheel carried by said arm, buoyant means operatively connected to said arm to influence the effective operating pressure of said wheel, said buoyant means being of sectional construction, the number of sections thereof being variable.

9. In a surface conditioning machine, an arm movable about a horizontal pivot, a plate movable in a horizontal plane supporting said pivot, a surface conditioning wheel carried by the free end of said arm, a iloat beneath said surface conditioning wheel and below the level of said plate, an upstanding stem carried by said float and adapted to be engaged by the free end of said arm, said stem coinciding with the center of rotation of said plate.

10. A surface conditioning machine of the class described, comprising in combination a conveyor, a base, a table supported by said base, said table supporting a part of said conveyor, a bed plate rotatable upon said table, a horizontal pivot supported upon and above said bed plate, an arm carried by said pivot, said arin carrying at one end a surface conditioning wheel, a tank in said base beneath the wheel-carrying end of said arm, a oat in said tank, means connecting the wheelcarrying end of said arm with said float, said means including a hat bearing.

1l. A surface conditioning machine of the class described, comprising in combination a conveyor, a base, a table supported by said base, said table supporting a part of said conveyor, a tank within said base, a bed plate rotatable upon said table, a horizontal pivot carried upon and above said bed plate, an arm carried by said pivot, said arm carrying at one end a surface conditioning wheel, a iioat in said tank, liquid in said tank, a rod connecting the wheel-carrying end of said arm with said float, and a dustguard surrounding said rod above said tank.

12. In a surface conditioning machine, an arm movable about a horizontal pivot, a surface conditioning wheel carried by said arm, and means engageable with said arm for limiting the downward motion thereof or for imparting upward motion thereto, said means comprising a stop adapted for engagement with an element of said arm, and air cylinder means for maintaining said stop in selected position or for lifting said stop.

13. A grinding machine comprising a plurality of grinding elements each individually automatically movable up and down with respect to the work and means for lifting said grinding elements comprising an individual lifting control for each machine and a simultaneous control for a series of machines.

14. In a grinding machine, as a sub-combination, a swinging arm, a grinding wheel carried thereby, a pressure cylinder engageable with said arm and being reciprocable by pressure means and rotatable by other means, a stop carried by said cylinder, said other means being adapted to position said stop with respect to the arm and said pressure means being adapted to move said stop and thereby move said arm.

15. A grinding head comprising a swinging arm, a grinding wheel carried thereby, a stem adjacent said arm, means for admitting air through said stem, a cylinder fitting over said stem and reciprocable with respect thereto, the upper end of said cylinder forming with said stem an expansible fluid tight chamber, screw threads on the exterior of said cylinder, and a stop threaded thereto and adapted to be positioned therealong by rotation of said cylinder and being engageable with said arm.

CHARLIE L. HAWES. 

